OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Briggs & Stratton Engines Potential Death from flywheel

Hi,

Now that I have your attention perhaps someone with more experience than myself can let me know if this flywheel is safe to use?

I've been reading lots of horror stories on the net about flywheels with broken fins causing total destruction.

This one is on my B&S 170432 Horizontal Shaft. Only the 2 fins that you can see in the picture are damaged. Chipped rather than completely broken off.

Someone has obviously been in here before and I suspect they broke the fins when removing the flywheel.

I'd appreciate any opinions.

Thanks

hello Horace,
I wouldn't worry about it but if you are worried about balance.
Get an angle grinder or file and cut same piece off in exactly opposite side....
If two fins are broken off. I brake two off directly opposite.
cheers
speedy

Don't be surprised that was also caused by a casting fault

Thanks guys.

Those are the alloy fins on the magnet, nothing too major to worry about. Cast iron flywheels usually only start being a problem when people do things like remove governors to increase the revs dramatically, on go karts etc. At higher rpm balance is important, not to mention cast iron is full of air pockets, which lead to major failure.

That flywheel is no where as dangerous as the one I seen here a few years ago where someone had pop riveted one together. Now that one was dangerous. Most flywheels are usually shrouded just in case of breakage so it is contained considerably.

G'day all flywheel lovers
I am compelled to say something here.

The flywheel is a critical component of small air-cooled engines.

As AVB has found, there are stupid and dangerous repairs to them.
ODK can not endorse balancing methods mentioned here.

From my experience, Manufactures test quality and safety.
Casting faults are super rare.

The vast majority of fractures occur with dodgy after-sale servicing
and home repairs.

We must follow manufacturer instructions!

------------------------
Jack

This I agree with Jack.

Many of the flywheels I have seen damage have been from techs taking shortcuts or not using the proper tools. So far in the 11 yrs of professionally servicing small engines I have only seen one flywheel failure. And it was this year when I came across a Briggs flywheel where the flywheel slipped from being under torque and the flywheel instead of shearing had rolled busting the center of the flywheel. This was an older design of the 21,28, 31, and 33 flywheel which Briggs redesign to make things better.

One biggest problems with DIYers and some techs is that they either under torque the flywheels or use an impact gun (rattle gun) to tighten these flywheels which induces problems. Another thing that makes me cringe is the use of a screwdriver or other object stuck in the fins so they can tighten the retaining nut or screw of the flywheel.

Personally I would never use a damage flywheel. I have replaced several old Briggs flywheels that were damage by hammers where someone was trying to remove the starter clutches. Of course I have that removal and installation tool in my tool now collecting dust.

in thousands of machines over the years I have had one briggs and stratton flywheel explode and it was all contained within the starter cowling, there was no apparent reason for it letting go, the part that wrote the engine off was a broken piece of flywheel did snap the ignition coil mount off.

Thanks Guys,

I'd be happy to replace the flywheel if I could find one. I know its a discontinued part and the only 2nd hand ones I've been able to find are in the USA. Postage is very expensive so I'll keep trying to find one in Australia.

If anyone has a flywheel for a 7HP 1979 Briggs model 170432 for sale please let me know.

Cheers.
H.

If it was sold here, there will be one out there in this country.
Importing from the U.S is a bit drastic.

But when is like this you just don't need to reuse it.

Easy to see where they went wrong with that AVB they should have used JB Weld before they riveted it LOL

I don't see the problem as long as it's balanced. American ingenuity right there.

MF - that's Aussie ingenuity - Speedy did that on a sprinter

Think AVB nearly had a coronary at the time

I wouldn't do it due to potential damage, but there is low risk of bodily damage by it exploding since its all contained in the cowl. Biggest risk is a chuck hitting you in the eye

Now I knew someone would find the post here. And no I have found that bad here yet but with extremely lightweight Briggs flywheels it happen at anytime. I got one those flywheels in the recovered parts bin that is in nearly new condition where the idiot brought the mower from Walmart, put gas in it and started mowing his lawn. In less than 30 thirty minutes he bent the crankshaft and threw the rod. The rod broke and put a hole in the crankcase all because never put oil in the engine.